Nah...get a Frost...much nice Utility and Rocks with Defense missions and Boss fights. That damn Ice bubble....the Shizzle! Took me about 50 runs to get all BP's but was well worth it.
Dont get me wrong, Rhino is nice, but Frost has soooo much more utility! That bubble lasts for so long, and cant be increased with Mods... = perma slow for mobs or bosses. Makes defense missions and absolute breeze! Just bubble objective, you can shoot out from bubble but no bullets come in...although that counts for mates bullets as well. Also nice to create barrier in doorway to clear a busy room

Just fight inside bubble

everything is in slow mo!

With frost you solo most bosses easily.
I have:
Excaliber - maxed
Ember - maxed
Ashe - around lvl 12, not really played much til recently (fell in love with frost)
Frost - Maxed
Banshe - Unranked
Almost finished:
Saryn - need 1 bp
Vauban - need 1 Bp
Pm me in game, we can hunt any boss you like pretty much
Banelight out! o7