I have been using toe clips on my old bike, but now that I got a new race bike I am thinking about trying something new, such as the SPD. Because I like the idea of being able to walk a little bit when I get of the bike. Specifically, I am looking for the Shimano PD-A600. But I saw most people here use the Look/Speedplay/SPD-SL pedals for their race bikes. For racing and training purposes, would SPD work fine? Would there be a disadvantage for using the SPD for racing?

Yes

Yes, it'll be fine. Use still-soled shoes. But expect people to tell you that bona fide road pedals will give you 1,200 extra watts, allowing you to cruise along at 37 mph on the flat in your granny gear.

Racers wear loafers or flip-flops to walk to race registration, not their cycling shoes.

But those will work, they'll just be heavy and perhaps not quite as comfortable on long rides as regular road pedals.

Get Bona fide road pedals instead. Bona fide road pedals will give you 1,200 extra watts, allowing you to cruise along at 37 mph on the flat in your granny gear.

I have little rubber covers for my speedplay cleats that are easy to walk with on hard surfaces but still offer the performance of road pedals.

Bona Fide? Never heard of that brand. Italian?

Make sure to get cleats with some float or you might be hating life on longer rides.

No use eggbeaters they are as light as most road pedals and I use a Shimano m087 shoe. Not hardly a bit of difference in weight and how they work. You can walk all day in them too. Also I generally I can cruise in the flats on the small ring around 45 mph, I too afraid of going to the big ring.

I have two sided spd pedals on my road bike. I like being able to walk normally, and they are great for no-look fast clip-ins after stopping.

But I've pulled out of the pedals a couple of times when going full blast away from a stop, pulling up on the upstroke. I probably twisted my foot just enough to unclip. I wouldn't use them for racing, they just aren't secure enough for high wattage sprinting.

There are two types of shimano SPD cleats. Most people are unaware of this, and many mistakenly claim spds are prone to accidental release, when its not really the fault of the pedals. One type is a multi-angle release cleat...its for noobs and easy to pull out. You dont want that one. Get the other cleat and youll never pull accidentally.

sometimes pulling out helps prevent big accidents.

"For noobs" -- really? I thought they were for people who don't want to die in traffic. You want that one if you're commuting.

Standard - black SH51
Multi-release - gold SH56

Not really. I can unclip just fine. I've used the multi-release cleats. IMO they are mora dangerous than the regular cleats because they do tend to release when you don't want them to.

I've never had any problem unclipping with standard SPD cleats.

Indeed.

I have both SPDs for mountain and cyclocross and SPD-SLs for road. Each has advantages for their riding purpose (won't get into walking) but SPDs aren't as good for road and racing use.

Bona Fide = Genuine.

And I don't see why using SPD would be a problem, and I can walk just fine with SPD-SL cleats and cycling shoes.

I lol'd irl

SPD pedals are perfectly fine for road racing. I've used them for the past two seasons with no record of accidental unclipping.

Just remember to crank up the release tension.

The pedals that OP has weigh about the same as Dura Ace pedals.

I've never used the multi-release ones. The standard ones are fine, and easy to unclip at stops.

But, in an all-out sprint, I've unclipped accidentally a couple of times. Without meaning to, I must be twisting my foot a little too far. The cleats don't look worn. I'm going to try tightening the release adjustment. It's a couple of clicks from the easiest setting. If I need a little more force to unclip, that should help.

Edit--nosaj also says to tighten the release tension.

You really can't see if it is worn unless you remove the cleat from the shoe.
It is the beveled edge at the rear which becomes worn.
I normally unclip the right foot at stops, so it is the right cleat I wear out first.
When I unclip accidentally in a sprint, I know the cleat needs to be replaced.
I only need to replace one once every couple years.

I almost spit coffee on the screen

On this note, any of you guys using cleat covers? Worth it?