I haven't attempted yet,but i am sure i would cream the Bug guy. I am currently filling anything i missed in the "seen" category of my Pokedex,so when i record all the Pokemon the Elite Four have,my Pokedex will be full and i can upgrade immediatly. I have everyone but Azelf,who i am attempting to catch as i type. I got lucky with Uxie,not so much here....
that's what I'm doing now, too. Azelf will not let me catch him. I got him so far into the red that he was almost down, used an ultra ball, and he still got away!

Azelf has a capture rate of 3, so catching it is still a pain even though it has a sliver of HP left.
Dialga/Palkia is very easy of a capture rate of 30,
which is the capture rate of a Chatot and Chansey. This number is ridiculously high for a legendary.
However, in Platinum, Giratina has a capture rate of 3, so it'll be a challenge to catch.
Heh. I captured Azelf. I still have to catch Uxie, and I've seen Mesprit. I'll most likely import Master Balls from my Emerald version to catch Mesprit and Cresselia.
I caught Giratina w/ a Timer Ball. And Azelf in a dusk ball(at night and in a cave...) I'll go for Uxie and Rotom tonight.
I still need to see 7 pkmn. Togekiss, Rotom(i think) Uxie, Feebas(where do I see one?) Monferno(again, where do I see one?) Umbreon(same as previous two) and Swinub(again, where is it?)
Togekiss - Champion Cynthia
Rotom - Old Chateau at Nighttime (Talk to the TV in a room)
Uxie - Lake Acuity
Feebas* - 5 Stars Restaurant in Valor Lakefront, Collector Eugene
Monferno - Pokemon Ranger at Route 212 South
Umbreon - Collector at Route 212 South (Rainy Area)
Swinub - Route 216/217 in the Wild
*Feebas can also be fished in Mt. Coronet in the foggy area which leads to Route 216. However, it is very rare, as it only can be found in 4-6 tiles per day. [You occupy one tile] As a day passes, the area where Feebas occur change. In R/S/E, things were much easier, since Feebas's location was determined by the "Trendy Phrase" in Dewford Town.
Once you find Feebas, catch as many Feebas as you can.
Thanks. I'm not looking to catch a Feebas, although if I ever am I'll share records with a few friends and we'll all search at once.I'll have to go look for a swinub, and I'll battle the three trainers to see the other three and Cynthia to complete my dex.
I hate how hard they made it to catch Feebas...