I got the basilisk mainly due to the price factor. Paid about $60 back during 11/11 last year, and for the price paid really no complains. I am left hader and though this isn't a ambidextrous mouse, the ergonomics are comfortable enough for me. I hate RGB and just nice this mouse simple design without all the RGB nonsense(i even use my keychron k2 with the RGB lights off).
Like you said, supports both bluetooth or dongle connection. And again to bring up the RTings review, they tested click latency for dongle connection to be 10ms compared to 12ms in bluetooth connection, which is a totally negligible difference. Review link if you are interested
https://www.rtings.com/mouse/reviews/razer/basilisk-x-hyperspeed.
As for battery, i am currently using AAA battery for some slight weight reduction(get cheap ~$1 AAA to AA battery converter case from china sellers on shopee). Rough gauge of battery life base on my usage pattern, for cheapo GP battery sold by those ABC/Valueshop, 1 battery last about 10 days. For Eveready battery, 1 battery last about 2 weeks plus. For Duracell, the one currently still inside my mouse has lasted about 3 weeks and counting. Again YMMV but Bluetooth mode has much longer rated battery life compared to dongle mode so i have not bothered to use in dongle mode at all.
If i have 1 complaint, its that the Razer Synapse software is absolutely utter garbage. I encountered quite a few times the program crashes or restart while running in the background. Also it will occasionally pop up low battery notification even though i know its not the case since i just changed battery only. Honestly, fantastic value mouse if you dont need the extra bells and whistles like RGB, adjustable weights, cable mode and what not.