Mechas : Practical ?

For months and months AND months, whenever boredom hits the switch in my mind to "garbage-recycle-process" mode, the first thing that appears in my mind would be this bugger question :-

'How practical is a mecha, in terms of actual military application ?'

When I was a kid, I really like big giant robots - they are capable of demonstrating great strength, versatility and kickarse. But the process of growing up taught me that, nay nope it's impossible to build something like that in the first place.

I have left this issue to my left and right brain for discuss everytime this question kicks in, and none could came up with a clear answer for it. Here are some of the findings that were processed :-

(1) They are expensive to produce and maintain. Hell I can buy a whole panzer division with that, along with feeding the crew for months.

(2) They are quite delicate. Looks very to me. Just take out their arms and they are practically walking tin cans with the potential to become an iron coffin. Or just take out only ONE of their legs and they are truly tin cans.

(3) They are big and tall, so everyone sees them. I mean, it's not good if EVERYONE sees them. It's as if it carries an imaginary giant "HIT ME" sign whenever it goes. Also don't fit in small spaces, and mayors hate them.

(4) They fly. Yes, given the point that it's an advantage over ground units, but throwing in the 'bonus' of it being big, tall and obvious + extremely vulnerable blind spot at the back (where most of the time the jetpack is installed, ironically), it's suddenly not so much of an long-lasting advantage anymore.

(5) Some of them can actually transform. That's going into the treasurer's tab for extra research on how to fit all the parts from humanoid form to some vehicular form. And besides, it kinda beats the purpose of making it into a humanoid form if it has a vehicular form and still can perform combat equally.

(6) They were made to look cool and flashy. By far the only fact that sounds decent to me. Well, at it's own era the Spanish Armada looks cool and flashy too.

......

But that doesn't mean I despise mechas for being scrap metal or something - there are those that I actually find practical. Take, for instance, the design of the Landmates in Appleseed, which fantastically demonstrates great manueverability, speed and endurance, and can be deployed into various kinds of battle environments. If there's anything the government should invest into, it's that.

I guess it won't be that soon before we humans can come up with an actual one that's practical - we're still in the bomb-defusing bot era anyway. Maybe the aliens out there knows how, but if they invade us with that, I think we know how to deal with them now...