People keep saying that these putters either are guaranteed or are "more than likely" to hold their value. In the short run sure, probably, but in the long run? Talking 20,30,40 years? Why would they?
In the short run there will probably be enough demand in the marketplace to keep the prices up (assuming the market doesn't get over flooded with volume at some point, which could happen), but in the long run history suggests that demand will wane when a new kid arrives on the block.
Look at macgregor or Wilson staff, they were golf industry MONSTERS once upon a time, where are they now 30-40 years down the road? One has been spun off and the other is holding on to market share by the skin of their teeth.
The point is that tastes change, demand changes, markets change, products change, companies change, our perception of companies or brands change, and as technology changes a once valuable commodity can become nearly worthless overnight, look at what synthetic rubber did to the market for natural rubber once upon a time, why should a putter be any different?
Look if you want to buy an expensive putter or headcover because you like it or want it or can afford it then more power to you, but if you're buying it because you're convinced that it will never go down in value EVER then you're out to lunch.