(First post!)
Modchip installer here: The best chip depends on your console version. The original 30001 series didn't have any official modchips until the v4 came out, best one for that is the mars pro gm816-hd. There are two motherboard versions, bios gap and no gap. One is moddable with a matrix/modbo but it's extremely rare to find one, thus the need for a mars pro.
The 30001R and 35001 through the 39001 work best with the modbo 4 v1.93. There is also the modbo 750 v1.93, same thing just a different color pcb. It's also worth mentioning that some 30001R's are actually v4's.
The 50001 thru all slims work best with a matrix infinity v1.99/2.0. Do not recommend a modbo in a 50001 because of mechanon crash, it happened to me so many times over the years. The matrix v1.99/2 have their own oscillator, no need for a cx point. Do not use a modbo 5, it says v1.93 on the pcb but it's something entirely different. Whoever manufactures the modbo 5 is not part of the modbo brand, they stole it for brand recognition and to increase sales. Hope this helps!