The problem is that the line of play causes Runner to have 2 credits and a tag, and CtM to have 0 credits, before last click. (Because when you run my SSCG, I'm going to rez it to avoid giving you 10 credits. It still makes sense to go check the second remote at this point, in which case trashing it is still also the best thing to do.) The last click wouldn't be a siphon. At 2 credits, with a tag, your options are to either clear the tag or take a credit, leaving the siphon in hand.
This is why I think Hand 8 is still keepable. Even in the worst case scenario from the Runner, the Runner hasn't actually advanced towards a win-state, and has in fact gone the other direction. The downside is that you also have no credits, but only in that exact counterplay from MaxX. Lots of other scenarios leave you more favored.
To put it another way, the floor isn't that low, and the ceiling is high.
That may be true, but it's also nothing that I said. I've played DLR Val a year ago and there's a DLR MaxX player in my local meta. I understand that the actual point is to siphon them into the ground, but they are also trying to advance a board state as well. Trading two cards and 7 credits and a tag for two cards and 6 credits is not a favorable trade. Especially against a Corp with a strong econ from 0 like CtM.
EDIT: My ultimate verdict is Keep, but only because the hand is not actively bad, and it's so easy to mulligan into unplayably bad hands as the Corp. Additionally, mulliganing as Corp is a flag for the Runner, telling them that it's more likely that you don't want the hand you have. Keeping a hand as Corp implies that the hand is good on its own and thus A) Doesn't have agendas in HQ and B) Has a game plan that can be executed.
I generally keep about 60% of Corp hands, and 40% of Runner hands (or less). As was mentioned earlier, Runners have a better time of playing out from a 'bad' start, whereas Corp can get flooded and end up doing absolutely nothing before losing.