Upgrading and Integrating

I currently use a Jolida 302b to amplify the signal produced by my Arcam Alph 7 CDP and ultimately power my Spendor S100's.
I'm thinking of upgrading to the Musical Fidelity A300, but would like to hear opinions on this move vs shooting for an MF A3 CR and running it through my Onkyo 777 as a preamp until which time I can afford to purchase a separate preamp. Believe it or ont, the signal path in the Onkyo is comparatively (to other HT Recs.)direct, and as a preamp, it isn't all that bad. But is the A3 CR a dramatic step up from the A300????????????
The MF A300 integrated is much more detailed and transparant than the Jolida unit, sounds like a good move. I would not use an Onkyo as a preamp for A3CR amp, you would be wasting a good amp. If you want to get closer to
"audio nirvana" your next step after A300 should be DAC upgrade like Bel Canto 1.1, This would be very noticeable
upgrade in sound quality, biggest improvement for money spent.

Yes the A3CR amp is noticeably better than A300 integrated,
but you must upgrade DAC and preamp first to hear the improvement.
Depends on how long it will take you to make later upgrades. It also depends on whether you want a good sounding, well balanced system now, or a better one in the more distant future. The distant future of course depends on how long it will take you to upgrade. I like Megasam's suggestion, but i also think you'll find that the amp alone will greatly improve your sound. If I were you, I'd order all three from AudioAdvisor and play with'em for a couple weeks.