what kind of diving do you plan to get into. If you plan on staying in the recreational realm then you can grab any NITROX ready computer. But if you intend to switch to technical diving and cut your own tables you can save a lot of money and go with a standard wrist mount depth guage (scubapro digital depth guage) or a computer that goes into guage mode (scubapro aladin tec 2g). I personnaly use the tec 2g in guage mode and have not had any problems with it; plus scuba pro has great customer service.
As fo shopping at your LDSI’m 100% for that. the online shops will give you a cheaper price, but it’s the LDS where you will go for service, advice, dives and to BS about diving.