Yes they are all valuable. Ranging from extremely-valuable to barely-of-value.
People will come in here and tell you to look for VCVC or CVCV patterns (C = consonant V = vowel) and/or that Q, Y, Z, & X are bad letters, W, U, K, J, V are semi-premium letters and all the rest are premium letters, but i would suggest you find out trends and patterns yourself by reading the main LLLL.com thread here and studying the prices that LLLL's sell for. Could also check out LLLLSales.com and fool around with the various search options. Just remember there are lots of variables within LLLL sales that can affect their price, from age or letter-quality to pronounceability or to the marketplace that they were sold on.
well most of the LLLL.com that are dropped these days may not be considered as valuable because at present time you might only get a $ or 10 in return... (considering that the premium domains most probably wont be dropped) but once the industry gets back on track... then yes LLLL.com are really valuable...
i had seen people selling them for like 50$ a pop as the minimum,
but now its too less
but again you never know....
I think he means it was registered 5 years ago. If that early date shows on whois then there is a little bit of domainer interest there. It would be a sign (but not a sure one, by any means) that it is better than average because the better domains generally are registered earlier.
"Do all LLLL.coms have value" is a major subject of debate here, with strongly held views on each side. Here is the link for the main thread, the most recent page, you can go backward from there. There are nearly 700 pages so you are not expected to read the whole thing.: http://www.namepros.com/358387-the-llll-com-sales-discussion-thread-698.html#post3599560
There also was a LLLL.com buy-out thread that went over 1000 pages before it was retired in November 2007, the last month when LLLL.coms were generally available to register. A few drop each day now and those who dislike LLLL.coms are praying that thousands will be available to register again soon. 300 dropped one day last week and it took several days to clear them, but now more people are trying to catch them and they are taken very quickly. You can buy LLLL.coms very cheaply if you watch the sales pages here or elsewhere. But be prepared to hear people tell you that you are buying junk. Don't worry about it too much, make up your own mind, choose the best available within your budget (that could mean the best cheap ones, if that is what you think is the best investment) - and be sure to diversify!