|Just get some better glasses Bruce, not bigger cards|
One of the things Dave talks about a lot is a unit "making its points back". Now, this is a very easy way of evaluating a units performance in a game - if a unit cost 200 points, has it killed 200 points worth of stuff? If it's killed more than that, it's done well, if it's killed less than it hasn't.
However, we've talking the last couple of weeks about how it's a very narrow view of a unit's effectiveness. Anyway, here's a couple of examples of when it's not always a useful benchmark...
As we all know, these guys can arrive late or in the wrong place entirely. It's also possible that even if they do turn up in the right place, they might not "make their points back". However, what they do is put that element of doubt in your opponent's mind when deploying. They also make your opponent want to keep moving their vehicles so that you don't get autohits on them in combat, thus lessening their firepower. Then, when they do arrive, they usually take out a critical unit (eg a squad sat on an Objective) or a dangerous unit that's difficult to take out at range (eg tanks) Plus, your opponent then has to deal with the Scouts since they can't risk having them run around in their backfield and anything focusing on the Scouts isn't focusing on the rest of your army.
Thunder Hammer/Storm Shield Terminators
This particular example if from a game two weeks ago between Dave's Space Marines and Keith's Grey Knights. Dave's Termies Deep Struck in right next to Keith's Purifiers whose Rhino had been immobilised the previous turn. The threat from the Terminators meant that Keith shot pretty much his entire army at them before charging in with the Purifiers. The Terminators were promptly wiped out. Clearly the Terminators hadn't "earned their points back" but they had saved the rest of the army from being shot and had also cost the Purifiers a turn of movement towards the rest of Dave's gunline.
Yep, the Heavy Flamer is great and of course the Multi-Melta is brilliant. However, the best thing about Speeders is their ability to block enemy units. It's entirely possible that the Speeder won't actually kill anything during the course of a game but if it can slow down an assault for a turn or two then that can make all the difference.
For me, this is the absolute best example. When did you ever have a Rhino kill 35 points of stuff? Never. But its ability to move your army around quickly and safely is worth every one of those points. Even after it's disgorged its squad it can make a nuisance of itself by blocking the enemy and tank shocking.
Is there a better 'force multiplier' out there than the humble Rhino? Lower than a King? Aw, you get nothing for a pair; not in this game!