Thanks sailing dog! But just that jacket kind of breaks the budget for me. I don't think I can afford to spend $500 on a jacket I might only need for this sailing trip -- I was hoping to spend no more than $200 to maybe $300 altogether! I mean, we'll be off the west coast of Africa all the way up to Gibraltar, and the Mediterranean should be even calmer and nicer. Do I really need top-of-the-line gear?
No, you don't need top of the line gear, and you can often find good gear on sale. I regularly check the clearance racks at Defender and West Marine for just that reason. The day-to-day jacket I wear is a Gill '3-Dot' coastal jacket, and it works pretty well--and retailed for $200, but was on clearance for $40.
The key features I'd look for in a jacket are the inner/outer sleeve cuffs, the high collar and hood, and good retroreflective patches on the chest, shoulders, sleeves and hood. These are features you're not going to find on most terrestrial foul weather gear, so you do need to go with a marine specific vendor.
The Grudens gear is excellent, but not as comfortable, especially in warmer climates.
As for the Helly Hansen gear, I'd avoid them. I had one jacket made by them and the inner coating that provided the jacket with its waterproofness flaked off and left white flakes on everything I wore when I used it. It was a horrible PITA and it lasted less than a year. The Gill and Musto gear I've used has been much more durable.
I'd point out that good quality foul weather jackets are an investment...they last for years if you take care of them. My Musto jacket is six years old... and that breaks down to less than $60 a year, and it still looks almost brand new. The Gill jacket is now on season three, and is used as my almost daily wear windbreaker/light jacket and is less than $13 a year.
DrB's point is a good one. Don't underestimate how cold a night watch can get, especially if it is raining and you don't have a full cockpit enclosure to deal with the rain. Add the windchill from a constant 20+ knots of wind, and you'll be very glad you dressed in layers and have good foul weather gear to keep you dry.
BTW, IMHO, the jacket is far more important than the bibs.
In many cases, unless I know I'm going to be sitting in torrential rains in the cockpit, I don't even bother with the bibs. If you have to decide between getting a really great jacket or a mediocre jacket and bibs...I'd say get the jacket... BTW, I own and use a set of West Marine Third Reef bibs, but have a top-of-the-line Musto jacket. The jacket gets used about ten times as much as the bibs. Keeping the torso and core of your body dry and warm is key to preventing hypothermia and staying comfortable.