My Transformers collection is limited to combiners/gestalts - I have all of the G1 sets and a lot of the stuff released only in Japan - like Dinoking, Liokaiser and Landcross...
Anyway, since they aren't true "gestalt" type combiners, I had been passing on the Power Core Combiner 5-packs.
When I was in a local WalMart this morning looking in vein for new Star Wars stuff, I noticed quite a few of those 5-pack sets in the clearance aisle, so I dug through them and I found a Grimstone/Diniobots set - I went to scan it at the price scanner and it rang up $10!!!!
I don't know if this is a chain-wide price (I had heard that they were being sold for $13 last week) or if just this store over-discounted, but the $10 price tag was too good to pass up so I also scored the Combaticons, Protectobots, Destructicons, Destrons, Constructicons and Rallybots - all for $70 + tax. Not bad. Definitely better than the original price tag of $140 + tax!!!