Hey guys, I'm not an F-series owner, but i've got a relevant experience.
I'm planning on going on a month or two long tour this summer, and I'm looking for a backup for my main amp, an Orange AD30TC and 2x12 Orange cab w/V30's. I wanted something with two channels, EL84's, big sound, takes up little room, and doesn't weigh too much (since it would be a backup). Poking around yesterday at GC in West Palm I saw that they had just gotten in a bunch of Lonestars (like 6 of them), a couple of tridents, and one F-30 combo.
Now, i had played the Trident before, and knew it wasn't for me at all, but from what i had heard, i was really interested in playing the lonestar. But when i saw the F-30 sitting there i plugged into that first. I hadn't even considered the F-30 despite the fact that it pretty much fits all the criteria that i wanted for a backup amp.
Long story short, I sat there and played the F-30 for an hour straight, and never plugged into anything else. Man that little amp was killer. I love the simplicity of the controls (other than the reverb, the control setup is the same as my Orange, although from what i've read the knobs interact differently, maybe). I love the versatility of the amp. So many sounds were available from just two channels. I like to set my Orange up live with one channel being a lightly overdriven clean, and the other being a fuller overdriven sound. That capability was there in the F-30. The addition of the contour boost was even better. I can imagine as a solo boost or as a slightly different voicing option, there are very few sounds that wouldn't be available in this amp.
My only complaint (which is not a big one by any means) was that, as i turned the gain knob up, the overdrive became more "compressed" at higher levels. I think this is mainly due to the fact that the F-series is mean't to do much higher gain than my Orange. With the Orange, the gain stays very open sounding and uncompressed, even at high volume and gain settings, but the gain from the F-30 was almost twice the level of what my Orange is capable of.
Either way, I think i've found my backup/next amp. If the sounds that i was getting out of it semi-cranked in the loud room at GC, and through the 1x12 V30 in the combo are any indication, this amp will absolutely destroy running through my Orange 2x12 V30 loaded cab.
I've got half a mind to drag my cab and guitar back down to GC, just to check it out. *rant* I had to use some Hum-equipped LP standard, because for some reason, that GC doesn't have ANY P-90 equipped guitars at all. Nor do they have ANY sets of guitar strings from ANY brand with a wound G string.

*rant*