OK, Just a bit of input from someone who does both Bio and Brisa.
Firstly, I personally don't believe the 2 to be even comparable. They are totally different and sit very well alongside one another in a portfolio for different clients, so I would never choose one over the other. Yes, they are both gels, but IMO they are as alike as gel versus L&P.
Yes, if you want a change of colour with Bio you do tend to remove and replace. Actually I do occasionally infill but it is actually quicker to remove and start again! From when a client comes through the door, the gel is off and the nails prepped within 15 minutes, and are lovely and strong waiting for another application. It doesn't take more than 5 minutes to soak the Bio off....and I personally find this quicker than filing down! The nails are in contact with the remover for so little time they suffer no drying or adverse effects.
However, if I have a client who is tough on her nails, has french finish week in week out, never changes her style or colour and I have to regularly extend, then in my opinion, they are better off with Brisa. It is tougher on a heavy handed clients (although Bio extends very well and is very durable, duie to a good level of flexibility) That, by the way, is not to do with lifting.....I get no lifting ever with Bio (but do on occasion with other products). Its more to do with the strength of the enhancments and full on nail breakages!
I usually get any new Bio Clients converted to NNO's within 3 or 4 services (if they needed extending to start, the nails are grown out to a lovely length within a few weeks) and then the overlay is usually sufficient to protect against any breakages.
My colour clients aren't happy with polish over gel.....they do not believe it stands the test of time as long as a UV cured colour gel, and I have to say I tend to agree. Yes polish last longer on an enhancement than natural nail, but whether a file off or soak off colour gel....it does keep its colour and brilliance so much longer than polish.
To be fair.....the majority of clients for me are Bio Sculpture, and that has been driven by customer demand. I am lucky in that a huge proportion of my clientele are regulars, and new ones have come from word of mouth, asking for Bio Sculpture, as they love it on my other clients they have seen, but I wouldn't be without Brisa in my portfolio. I personally believe that having both has paid dividends and would pay for itself for any tech, so my best advixe woiuld be save some pennies to get both in....I think it will pay for itself in the very short term in a larger and loyal client base.