Is it better to refrain from using produce of Eretz Yisroel, or to follow the procedure for separating Terumos and Ma’asros as described by the COR, Toronto’s Hashgocho, or is there an alternative process?
In general, one should not eat fruits and vegetables from Eretz Yisrael without a good Hechsher.
Vegetables may be eaten after performing the procedure of Terumos and Ma’asros. Fruit, however, may still have a Kashrus problem, due to a concern of Orla.
There are some people in Chutz La’aretz who have the custom not to eat anything produced in Eretz Yisrael (this includes packaged foods as well, such as wine, cookies, Matzah, etc.) and this was the Rebbe’s Minhag too.
However, this is not necessarily a path for the public, aside from the fact that in today’s day and age it is often difficult to get a variety of products with high standards of Hechsheirim produced out of Eretz Yisrael.
שו”ע יו”ד שלא.
אגרות קודש חלק ט עמוד כח. וראה מקדש מלך א ע׳ 43. שיחת ג׳ ניסן תשל״ב. התוועדויות תשמ״ז ב ע׳ 115.