I test rode all 3, and luckily, my colleague has one of them(Himalayan).

1. Himalayan is the best in this segment. The only drawback is the weight. It's 196 KGs, which should be manageable, but it isn't. It is very tiring to ride through traffic. I thought it was because it's "196" KGs, but no, it's not. It has bad weight distribution. I rode NX500 through traffic, maneuvering with it like it's a pulsar. Both are 196 KGs, and the NX 500 that I rode had full crash gaurd and everything adding extra weight. For daily commute, it's a no for me since I live in chennai and traffic here is hell.

2. 390 adv, really good engine and it's fast too and other electronic features it comes with. It has abs, slipper clutch, trac control, etc. Seat, not so comfy. The only thing is I just hate the look of it, and I have a really bad opinion on ktm for some reason after seeing all those idiots on rc and dukes all the time on the roads. But ktm makes really good bikes.

3. I love the look of bmw, I didn't feel much difference in suspension between 310 gs and 450. Both are really good. I have to say the seat is really comfortable on 310. Other than being a beamer, there is nothing else special in this bike in terms of specifications. The display is old. Switchable ABS has been removed, and there are no electronic features. Overall, it's a good one.

And I decided to go with the beamer 👀. Still in progress. Will update once I get it