but how much (if anything) am i sacrificing from a disposable n95? !

Great video from the Mask Nerd on this exact subject. The TL;DW is that once you have a quality respirator (e.g. KF94/N95) the quality of fit far dominates filtration efficacy. It's worth noting that it can be easier to get a good fit in an elastomeric (both because of their construction and because it's trivial to do a positive and negative pressure fit test without any equipment), but if you can get a good fit with an N95 you should be good to go for everyday situations (KF94s are difficult to get a good fit in because of the design, so I'd recommend N95s when possible). Of course, part of the problem is the difficulty in determining the fit for disposable respirators, since quantitative tests are out of reach for most (that's actually something the guy who made the video is working on). Maybe someone else here can speak to qualitative tests, which are more accessible. You can also see if there's a mask bloc in your area who may be able to direct you to a community fit testing opportunity.