Rect-o-verb or F-50

What are the tonal similarities and differences?
What has a better clean? Headroom?

BTW, I am comparing the combos (1X12)

Ive had both and I would say for clean headroom its the f-50, the recto breaks up sooner. But for full on distortion, the recto no doubt

I owned a F-30 and now currently a Rectoverb, so my comparisons don't exactly apply but perhaps useful to you.

Clean tones I actually prefer the Rectoverb, namely because of Pushed mode (which is pretty much an OD mode) but the F-30 was great as well. Even with only 2 EL84's, the F-30 had a very decent amount of headroom for pristine clean tones at higher volumes.

Distortion on the F series is much warmer than a Recto, but still has the classic Boogie menacing roar. To me, the tone fell smack in the middle between a Mark IV and the Recto line. Honestly, I miss my F-30 for a tighter high gain rhythm tone, where the Recto is bigger and a bit looser sounding. That said, the voicing of the F series' distortion wasn't very usuable unless I had Contour mode engaged; it was more of a fuzz/OD without it. Another downside, depending on if you're a tweaker or not, is the tone stack on CH2 isn't very responsive. It affects the gain structure rather than overall tone. It's a cool design, but in the end I simply needed more versatility. If I could have afforded to keep my F-30, I certainly would have. Awesome amps for the money.

For lead playing, the Recto in Red/Vintage gets the nod. The F-30 was a bit lack luster for leads.

As stated before, the F50 will have a better clean (I think a fantastic clean)channel, two modes for channel two. Normal mode is O.K. with say a Strat for some bluesy type breakup to what I would call a basic rock sound. The Countour Mode is where the money is at, kind of markish sounding but again you will have to spend some time tweaking. It doesnt clean up with the volume on the guitar, either ON or OFF if the gain is past 11:30. Not a big deal if you spend some time with the amp. I like this amp best when plugged into an extension cab like a 2X12 or even better 4X12, and the effects loop is pretty good as well.
The rectoverb is a totally different beast. Where as the F is sharp and tight and crisp, the Verb is a loose sound. I liked this amp when I was the only guitar player in a band, it fills a lot of space. I really dig the "Pushed" mode on the clean channel. The normal clean is kind of lacking if you dont spend some time turning the dials, but I can get some funk out of it. Channel 2 is the heart of the beast. I used to use only Vintage mode, but now I am liking Modern with the treb and pres. rolled back. If you use guitar, cord, and a couple of pedals, this is your amp. If you like to use different types of pedals and gain boxes for your sound, I think you will be better off with the F. just some thoughts.