At the time of writing this article, we had no access to DTF and Elmers board, so we have based our numbers against the thread :
http://www.flitetest.com/articles/comparing-foam-board
Which has some real good work done in documenting the parameters.

Weight

Weight is the most important criteria, in the aeromodelling application of paper laminated Foamboards.  We measured 10inx10in piece of available materials and weighed them .

 

32Gms.	26gms	16gms	44gms	39gms

 

FliteBoard Pro.

10inx10in piece weighed : 32gms.
In other terms, the sheet weighs :
0.32gms/sq inch  or  46gms/sqft  or 500gms/sq Mtr (GSM)
A 20”x30” sheet would weigh : 192gms.

FliteBoard Lite.
10inx10in piece weighed : 26gms.
In other terms, the sheet weighs :
0.26gms/sq inch  or  37gms/sqft  or 400gms/sq Mtr (GSM)
A 20”x30” sheet would weigh : 156gms.

Unlaminated Depron 5MM.
10inx10in piece weighed : 16gms.
In other terms, the sheet weighs :
0.16gms/sq inch  or  23gms/sqft  or 245gms/sq Mtr (GSM)
A 20”x30” sheet would weigh : 96gms.

Alphaboard 5MM.
10inx10in piece weighed : 44gms.
In other terms, the sheet weighs :
0.44gms/sq inch  or  63gms/sqft  or 675gms/sq Mtr (GSM)
A 20”x30” sheet would weigh : 264gms.

Alphaboard 3MM.
10inx10in piece weighed : 39gms.
In other terms, the sheet weighs :
0.39gms/sq inch  or 56gms/sqft  or 600gms/sq Mtr (GSM)
A 20”x30” sheet would weigh : 234gms.

Dollar Tree FoamBoard :
10inx10in piece weighed : 19gms.
In other terms, the sheet weighs :
0.19gms/sq inch  or 27gms/sqft  or 300gms/sq Mtr (GSM)
A 20”x30” sheet would weigh : 115gms.

Elmers FoamBoard :
10inx10in piece weighed : 40gms.
In other terms, the sheet weighs :
0.40gms/sq inch  or 57gms/sqft  or 600gms/sq Mtr (GSM)
A 20”x30” sheet would weigh : 240gms.

Summary:
Without any doubt, the Dollar Tree foamboard is the lightest of the foamboards. Unfortunately it is not available outside the US. Even within the US several modellors have been using Elmers Brand of Foamboard, which is almost twice as heavy. Scratch builders across UK, Europe and Australia have also struggled to find a material that weighs like the DTF board and have used heavier materials.

The closest to the Dollar Tree Foam in weight is the FliteBoardLite.

 

Strength

Inspired by the Dollar Tree Foamboard comparison done here: http://www.flitetest.com/articles/comparing-foam-board

We took a 10”x20” sheet , laid it up across two piles of books and added weight till it broke down. The spacing between the books was kept at 16” .

We used these values so that we could matchup our results against the test results on the above comparison article.

 

 

 

Conclusion

 

	DollarTree Foam	Elmers Foam Board	FliteBoard Pro	FliteBoard Lite	Alphaboard 5MM
Weight/Density	~300GSM	~620GSM	~500GSM	~400GSM	~675GSM
Colour	White	White	Cream	White	White
Breaking Strength*	1.6Kg	5.2Kgs	4.5Kg	2.6Kgs	5Kgs.
Waterproof	No	No	Yes	Yes	Semi
Thickness	4.76MM	4.76MM	5.5MM	5.2MM	5.5MM