Levicom has used more than one manufacturer.
The 500W (shown
here), 450W and possibly the 350W are low-end Topower, similar to Aspire and not very desirable.
The 400W is by Wintech and may be good quality.
The 430W is definitely by Channel Well and should be excellent because it's virtually identical to the Antec True Power.
I don't know who makes the 420W Levicom, but both Topower and Channel Well have produced 420W models. However if it's a Channel Well it's from their ATX-suffix line, which is 3-4 notches below their A- (Antec True Power) and B- (Antec Smart Power), although I don' t know if it's better or worse than Channel Well's ISO- line. If the 430W Levicon isn't much costlier, choose it over the 420W; even a 380W (also like Antec True Power) may be better than the 420W.