I no longer collect sets, for several reasons
1, I don't like every design in a series but as I was collecting the series I 'had' to buy the ugly coin to keep the set going.
2, Unless you get them at issue price you will get gouged on the secondary market trying to fill gaps from earlier releases
3, You are at the mercy of the mint, if they want to release multiple mintmarked versions of the coins for example, you have to buy them to have a 'complete' set
4, Series like the Lunars have started to show quality issues such as milk spotting, damaging the reputation of the earlier coins in the series and potentially putting off current collectors and future collectors from the series.
5, I never look at the series anyway, the ones that are ongoing are difficult to display as you need to leave space for the following coins. The series that are completed tend to get put away and I never see them again unless I am looking for something else.
6, Series like the Kookaburras were hit when the Perth Mint re issued them and made them available far cheaper than the secondary market and collectors were selling them for. They could still reissue the Kilo coins if there was interest
7, they are hard to invest in, you pay extra money to complete the sets when most of the money is on one or two key coins in the sets, when you go to sell you have to sell them as a complete set which limits your market to people who want the coins and haven't bought any of them, most collectors are usually after one or two coins to complete their own sets and don't want to pay for the extras.
As an investment: So really, it costs more money to collect a certain coin rather than just buying the cheapest coin available at the time. There is no guarantee that the coin will rise in value and even if it does, there is no guarantee that the Mint won't do something to screw it up (either by reminting, issuing multiple privies or quality issues). When you go to sell, the coins will be in worse condition than when you bought them, toning, milkspots, scuff on the capsules etc. and you have a limited market. You would be better off buying a roll of the key coins (Dragon, tiger) in the year of issue and just sitting on them for a while
As a challenge: There is no real challenge to completing a set, you just need money (once for a laugh, it was a slow weekend many years ago, I went on eBay to see if I could buy one of every RAM Mint set, of course you would be able to put together a complete set and have it delivered for around $2000+ ish, haven't tried it for a while but all the sets were available at the time for Buy-it-now prices and this included the postage, you could probably have gotten it cheaper if you put a bid on the active auctions and didn't mind waiting until they all finished). Most coins are available for a price.
For the satisfaction: There is not much pleasure in owning a complete set, the satisfaction of putting the last coin into place doesn't last long and once that is over you have to look around for the next set because just owning a set only keeps you excited for a little while. It is fun building a set but once the set is complete you might as well sell it off and start another one.
I had a few sets I was collecting;
The RAM 1oz Kangaroos, I was buying the 1990s Roos for around $35 to $50 and slowly getting towards the modern ones when they started slapping an $80 price tag on the new releases, dropped them quickly but I still buy the 1993s when they come up as they are a nice design and usually around $40 each.
The Perth Mint Lunars, I was buying a roll of each new design on release but then the Mint started putting on limits to the number you could buy directly from the mint, so I had to go to the secondary market and then Mint realised that they no longer needed the limits so they removed them again. The Perth Mint website kept crashing so I kept missing out on limited releases (I was going for the 2012 Lunar Dragons) and they were so limited that they were on eBay the next day for 3x the issue price. They released a privy that I had to go to Germany to buy initially, then they decided to sell them in Australia anyway. Then they started developing milk spots. All in all I am not sure how they maintain their reputation for good quality issues.
The Perth Mint Kookaburras, I was putting together a set but most were in the $80-$90 so I didn't get them. Then they released a load of reminted coins for $35 and I filled a lot of the gaps but gave up on the rest of the series.
Perth Mint Koalas, I was putting together a set as they were cheap and I would just buy one each year when I was putting in another order, then the koalas all started looking really odd or ugly so I stopped buying them.
I was collecting the Canadian $20 for $20 series but got ripped off on eBay on a pre order so fell behind and haven't caught up and now the series is cancelled anyway.
I was collecting the Royal Mint £20 for £20 as I had a bank account in the UK so I could just swap £20 in legal tender for £20 in specie. But then the Royal Mint decided that banks no longer had to accept the coins at face value, so what was the point? Gave up on those. As predicted the money grabbers went for £50 for £50 and the £100 for £100s etc. I got one £50 because I liked the design but I passed on all the others.
Perth Mint now just sells coins on hype and the hopes of flipping them quickly for $$$. I am not an active trader so I never get around to selling them before the hype dies down.
I still pick up Perth Mint coins to give as gifts but I no longer try for sets and if a better looking coin becomes available I give them out as gifts instead.
I have mostly switched to silver bars for investment, gold coins for collecting (World circulating currency, not commemoratives or .999 Mint products), world circulating silver coins for fun and the occasional mint product as a gift. Not being tied to any specific set is a relief, I know several $1 dollar collectors who are waiting for The Queen to retire so they can stop collecting the coins, the RAM is churning out so many coins in the $1 series that it is hard and expensive to maintain a complete set, most collectors are happy to say they have a complete set of QE2 $1 coins but after that they are quitting.
