I've gotten really lucky on some of them on Amazon, or I've bagged a 40% off FP offer, but nonetheless, despite the relative success of that twin strategy, my buying of the deluxe hardbacks is going one way - down!
Where before I'd look at a series and wait for OHC, I'm now more likely to be paperback only.
(One exception is the IDW Transformer OHCs as they tend to be 3 trades to OHC, so it works out about £10 per trade, on a £30 OHC.)
At the same time, the paperbacks have also gone up in price! The only solution is really: Buy less!