The first is that it gives your other Rigger creatures +1/+0 and haste, and the second is the more infamous ability of doubling up on assembling Contraptions whenever one of your Rigger creatures assembles one
As much as I can sit and advocate for proxying being bad for the ecosystem, I cant not acknowledge that the pieces of cardboard in many deckboxes are worth more than their weight in gold
Theres even sealed product for if youre feeling lucky, but make sure you act fast because this set is so beloved that it sells out incredibly quickly.
Combine it with cards like Boss's Orders to rearrange the board and take down two Pokemon at the same time
Bear in mind that there's usually a huge difference in value between a PSA grade 7, 8, or 9 card (generally mint condition to the naked eye) and a perfect PSA 10 card (absolutely faultless, even when viewed under a microscope from every angle)
We generally dont care about land removal, but every now and again the kicker cost will be relevant