For first mech keyboard most people here either try blue or brown. You should try both before making a decision. It's your keyboard and decision, so try all before making one.
can't go wrong with blue... the safe bet...
Go Red, if you want something "very different" from what you're used to... because what you're used to can get boring.
When you get used to Typing on Reds, is like a wh000shh feeling.... almost organic..
Typing on Tactile (blue/clear), is like staccato... and you kinda feel like you're waiting to feel the key-press complete... so that you can engage in the next frame.
I think it's best you go back to the store a few times to really get a feel for it... maybe bring a laptop plug it in, and play a few rounds of 10fastfinger/ typeracer.