This insta- buddy thing can be a legitimate concern in technical diving. Those not in the "know" consider technical divers as snobbish, because they may not immediately accept another diver on the fly.... it is not that at all. Generally, in technical diving, there is no going to the surface at any time, so there must be a thorough understanding of teamwork or self sufficiency, depending on the divers & dynamics of the dive. As a team, the members must be able to trust each other in an unforgiving environment. To be 2,000 ft back in a cave at 100 ft of depth & discover that you & your "insta- Buddy " are not compatible, is not a good thing & potentially puts both divers at risk. I, personally will not dive with an insta- buddy. I will usually require at least 1 open water dive, & a couple very simple overhead environment dives, before doing a more intricate dive. I am just starting to get into technical instruction, as my confidence level increases & in that case will have to deal with unknown divers,... but is done in stages to build the skills, trust, awareness, confidence & teamwork abilities.
Just my $.02
BTW, Shearwater computers are awesome. I have 2 stand alone computers & one as my rebreather controller. They are easy to use & very intuitive.