So a few of us are doing or are planning to do level 5 missions and I thought I'd share some of what has worked and hasn't worked for anyone else interested in 5's.
The Good:
Level 5's reward you MASSIVE LP compared to level 4's. This is the primary money maker and the reason for doing 5's. You can change LP into ammo, ships, mods, implants, BPC's...whatever makes you the most cash. I currently make about 100mil per mission from my LP, and no I'm not gonna tell you what I'm spending the LP on. ;) The individual mission rewards are ok (3mil or so for completing, 3 mil or so more bonus) but not uber impressive over 4's. Depending on the mission you can also get a lot of cash from drops/loot/salvage. There's a 3 part Rogue Drone mission that you can almost build a battleship from at the end if you loot and reprocess the drone poo, and other missions drop tags which can sell for quite a bit. Loot is on par with 4's, maybe slightly better for some missions. You are here for the LP, not the loot or isk rewards though.
The Bad:
5's are ALWAYS in lowsec or lower. If you can't handle the thought of pirates, gate camps, losing your ship (oh noes!), or even being podded (my implants, oh noes!) then stick with the lower income level 4 missions in hisec space where the game is much less interesting :) That being said, lowsec is typically ok to move around in if 1. you use a scout and/or 2. you use cloaks and/or 3. you're not hanging around hisec entrances. Gate camps rely on speedy locks and big alpha because they cant use any kind of warp bubbles to keep you from running. Don't be afraid to get out of hisec and try something a little more dangerous. :) It's like moving from the big city to a small town...people actually talk and want to know who's around them (and who wants to kill them in the case of EVE). I've made more friends in lowsec in a month than I have in years of playing before (even in 0.0).
The Ugly:
All level 5 missions that I've done have neuting towers or neuting ships. I originally did level 5's using logistics ships which could pump cap into my 2 battleships to keep them shooting, but I've found passive shield tanks to be more reliable and definitely less of a headache. The DPS in 5's can get plain sick (4k dps is the ceiling I've read). All missions that have ships upon warp in auto aggro the first ship they see (and I believe missile batteries can actually target multiple people), and not all missions have gates (to allow capitals in...yes, they think you need cap ships to do those) for you to leave your noctis or dps or whatever sitting at waiting to come in (hint, if the mission shows no "Ship Restriction" link on the mission page then it has no gate at the start...you warp in and everything starts, so if you're small logi ships warp in first (they will if you warp them together) guess who is tanking?!).
Ships:
Tengu tank is awesomesuace. I use 2 stealth bombers for dps and thus all 3 ships can run around cloaked (take your cloak off the tengu before you go actually do the mission to increase dps). I cloak the sbombers for spawns to make sure everything gets on the tengu. One of the first missioners I met in lowsec ran 3 Tengu's (one tank, 2 dps fit) very successfully.
One enterprising fellow (Zeb, I'm not sure of your username on here) used passive drake, osprey to help it shield tank (cloak on the osprey for hiding just after spawns), brutix (w. cloak I'm sure) and sbomber for dps. Lots of micromanagement, but his proof of concept that you could use ships cheaper than the reward for a single mission seemed to work for him. Not an efficient setup though.
I originally used Megathron, Abaddon, and 2 Guardians which was super micromanagement early on in the fight but settles out quickly. The BS's killed quickly and until I lost the Mega in a horrible mission I would recommend skipping (Fate of Angels) I was able to plow through most missions. A friend I've met in lowsec uses Abaddons/Guardians or Ravens/Basi's for missions and is quite successful.
Dominix repping has also been mentioned, though I'm leery of this just from the standpoint of having to move those dominix's around multiple systems.
Nighthawks and Ishtars are noted level 5 tankers, though I know the Ishtar can only tank kin/therm well (not sure about the NH, never flown one). One fellow I talked to runs Nighthawk/Tengu and switches which ship tanks based upon the mission.
Rattlesnakes are supposedly great soloers for level 5's, but that's a big expensive target you paint on your back flying pirate BS's into lowsec. Tengu's are more expensive, but much easier to move around than Rattlesnakes.
