Well to be fair, the Davions borrowed a lot of the Capellan Confederation for a while, so it's only fair.
The difference is that Liao seems to have set up a 'rent to own' situation. ;D
OK, ok. So per the earlier discussion of whether the Flea stacks up against other 20-tonners... I mean, it varies from version to version. Some, like the 19, are so hyper-focused on anti-infantry weapons that they'll struggle against other Mechs, even bugs, simply due to lack of range. Take that little monster- once that RL-10 is empty, it can't reach out past six hexes, period. Which is fine, except it's also not fast enough to press the issue against most other small Mechs- a bog-standard LCT-1V will run rings around that Flea and chew it to pieces with its medium laser, always able to either hold the range advantage or duck away to safety if it's getting cornered. So against that Locust, the Flea is garbage- but for its assigned role of telling the striking workers to get back to the factory, there's probably not a better Mech in production anywhere.
The other side of it is the FLE-4, which... I mean, its armor sucks on toast, and it's not very fast for its size, but how many bugs can claim to take a large laser hit and be in fighting condition the following turn? That's a serious punch against small machines, and respectable even for larger Mechs to deal with. From that standpoint, if I want rid of Wasps and Locusts, that's an excellent option for the job.
But, as with anything that size, if you're looking at using it more than once, you're in the wrong business. 20-ton Mechs just don't really have the staying power to reliably be around for a full campaign in-general, even in 3025. By 3050, with the return of pulse lasers to the battlefield, double-heat sinks to allow for larger salvos per-turn, XL engines allowing for fast mediums, etc., it's even worse on small Mechs. Is the Flea worse off than most? No, it's just as bad off as any- without high speed or jump jets, it's easier to hunt one down, but it's got the same thin armor problem all small machines have, and it at least tends to have greater firepower than its competitors, so it can at least make the enemy sweat a little on its way to hell.
Speed, armor, firepower, pick two. No 20-tonner picks armor really, so it's a matter of whether you need more mobility or weaponry. Fleas almost exclusively lean on the latter, and if that's what you need from your bug, it's a great option. If not, it's probably worth reconsidering your available options in favor of Stingers or something like that.
(Backing interest in a Hornet article, because as homely as it looks, it's a pretty sobering Mech to deal with if you're using similarly-sized opposition!)