Tough call when "one of each" isn't a possibility
Well... first question I'd ask you is if you're mainly a first-position strummer, or if you play higher up the neck. The HF-1 has 16 frets, whereas if I'm not mistaken both of the Kiwayas you mentioned only have 12. Then there's the matter of soprano scale vs. concert scale - personally I'm comfortable on both, but after years of playing mainly soprano I came to realize I liked the louder volume and longer sustain of the concert scale. So that's something to consider if either of those is a factor.
FWIW, Kiwaya does make a few sopranos with more than 12 frets. They're very nice ukes and I've come close to pulling the trigger on one a couple of times, but each time I ended up deterred by intonation issues. The issues were only higher than the 12th fret and the ukes sounded fine for strumming and most playing, but since I play high up the neck a lot I knew it would drive me crazy. This was on several different models - and as I mentioned in your other thread, I've only encountered a single Kamaka with intonation problems in 6+ years of playing (and too many Kamaka encounters to count). I know these are generally things that can be fixed, but I tend to want my ukes playable right out of the box.
That said - I know you're planning to buy from HMS so setup/intonation may not be a concern, but thought it was worth mentioning anyway.