Do you find the F3 clumsy for stealth? I find my CA-11s > Zoom F3 rig less conspicuous than CA-11s (on croakies) > preamp (with a belt clip) > Zoom H1 (in my front pocket). I just turn the F3 on and put it in my back pocket.
Maybe my problem is that I just fairly recently started looking for a replacement recorder and found the F2 and the (then upcoming) Deity PR-2 (when everybody still expected it to be stereo). Both of them seem to be sized perfectly tiny but have other issues that disqualifies them for me (mono). Quality-wise the F3 seems perfect. But I don't need XLR and certainly compared to F2 and PR-2 it's oddly formed. I must confess: I've never hold an F3 in my hands yet. What I did do is building a Lego block with the size of an F3 and it made me realize I very likely won't be able to get it into stricter venues the way I usually do. But then again: I also realize that security seems be less strict than in the past, so it will likely still be possible to get it in anyway.
I guess my current line of candidates is:
1. F3 (despite it's form factor)
2. H1XLR (for lower price and hopefully good enough quality, pending proper reviews)
A new candidate could be the upcoming Tascam FR-AV2, pending combination of specs, size and prize. Not sure where that will land in my list of candidates.
The good thing is that I'm not in a hurry. I don't tape that often and my next gig is either in February or March next year...
In the UK, at clubs and academy-type venues, I've always placed my recorder + preamp in my backpack's smaller front pocket (the mics go in my spare glasses case). When it's my turn to be searched, I walk up to security with the main backpack compartment wide open - and they are always happy to take a look and leave it at that. No one's ever asked to search the smaller pockets.
At theatres, you don't even get searched most of the time.
I've never taped any arena or stadium shows in the UK, but I've brought stealth gear to festivals twice. The first time, they only searched the large pocket. The second time, they were a bit more thorough, but they failed to spot the F3 behind a sandwich.
I've only been to two shows in the US, both in 2016: Pitchfork Festival in Chicago, and Sufjan Stevens at Red Rocks. The guy at Pitchfork was very thorough and found my pre-amp and zoom H1 (he didn't care and let me in). I was not searched at Red Rocks.
Tldr; I've only ever had issues with cameras before. No one really cares about audio gear (though again, I've never tried taping in arenas or stadiums).